Learn more about bees.

What are bees?

Bees are insects closely related to wasps. The main difference between bees and wasp is in their diet preferences: bees eat pollen for protein, while wasps eat other insects for protein. Given a bee’s need for pollen, a special relationship has evolved between bees and flowers, with bees playing an integral role in the pollination of many crops and plants. As a result, every third bite of food you eat is attributed to pollinators like bees , and pollinators contribute to crops valued between US$217,000,000,000 – US$577,000,000,000 to the global economy (see sources for Klein and IPBES). Most people are familiar with a few bees species—such as honey bees and bumbles bees—but there are an estimated 20,000 additional species of bees in the world.

To see beautiful images of bees, visit the USGS Bee Inventory & Monitoring Lab’s Flickr page.

Are bees in decline?

The simple answer is that scientists think so, but it’s nearly impossible to find conclusive proof. To know whether bees are in decline, we need to know how many and what kinds of bees were flying around before the present time. This data does not exist for the majority of the 20,000 bee species around the world. Scientist are concerned, however, because the data that does exist—while mostly for honey bees and certain bumble bee species in North America and Europe—suggests that various bee species are declining.

Life of a bee

Nesting

The majority of bees (70%) nest in burrows within soil, wood, or plant stems. These burrows are usually dug by a single female bee. Bees that live in hives—in the US that means only honey bees and bumble bees—choose hollow trees, crevices in rocks, or larger burrows found in the ground for their nest locations. Most nests are divided into cells, and each cell usually holds one egg and a small ball of food for when the egg hatches.

Life Cycle

Most bees live for roughly one year. Although we tend to see bees in their last stage of life as flying adults, this stage typically lasts for only three to six weeks. Most of a bee’s life cycle is spent in the dark, developing inside their mother’s nest.

Bees start out as tiny white eggs, which hatch into caterpillar-like larvae, which then turn into pupae, and finally emerge as the adult insects we know and recognize.

When mating, a female bee usually receives a lifetime supply of sperm. When it comes time to lay eggs, she can lay either unfertilized eggs, or eggs fertilized with sperm. Unfertilized eggs develop into males, and fertilized eggs develop into females.

Food

Bees eat nectar and pollen from flowers. When they’re newly hatched from their eggs, the small bee larvae eat mostly pollen mixed with a little bit of nectar. As adults, bees eat mostly nectar mixed with a little bit of pollen. Pollen provides bees with protein, while nectar provides bees with carbohydrates and some amino acids.

Behavior

Bees tend to be most active on warm, sunny days with low wind speeds. When you see a bee visiting a flower, it is usually busy drinking nectar or collecting pollen for its young.

Sources